The monoclonal antibody 1H1-A7 recognizes human germinal center-associated lymphoma (HGAL) protein. HGAL is expressed in germinal centers, spleen, thymus, and germinal center-derived lymphomas. HGAL is localized to the cytoplasm of cells within the dark zone of the germinal center and functions to enhance the activation of RhoA leading to negative regulation of lymphocyte motility. HGAL expression has been used to help elucidate nodal marginal zone lymphoma (NMZL) from cases of diffuse follicle center lymphoma. Additionally, HGAL expression was shown to correlate with survival in patients with diffuse large B-cell lymphoma (DLBCL).

The 1H1-A7 antibody recognizes the protein product of the M17 gene, the mouse homolog of the HGAL protein.